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Even with nothing else on it is doubtful a 1,000 Watt inverter will start the A/C. You're actually looking at a start-up surge that translates to at least 1800 Watts. With the usual efficiency losses, you can expect to fault the inverter with every attempted start.

And a 12 Volt system is hopeless for such big current draws, never mind run time. That 5 Amp AC running current will be more than 50 Amps DC, and will flatten two T105's to dead in short order if they do survive the 150+ Amp start surge. Looking at it in the simplest (and least accurate) way:

A/C and other things that use compressors can have a very high startup surge, as much as 4x the running amps. I doubt that either of those inverters mentioned will have the surge capacity to handle it.

You can minimize the surge by cutting the Compressor off by turning the Temperature as high as it will go and let the fan start first by it's self, then cut the compressor in. Once you got it going it's the compressor cutting in and out with the fan on constant.

The draw will over time will drop as you get the room temperature down the cycles will go down. There is a point that your better off to keep the compressor running all the time because the cycles are short and it'll draw more cutting in and out.

I think Coot was a little generous with the 50 Amps @ 12v, mine pulls about 70 Amps.

I have my fan on a " Delay on Make " timer cube and it will delay the fan start and a wall thermostat on a relay for the whole thing. The Fans on a A/C are big hogs by themselves.

You can minimize the surge by cutting the Compressor off by turning the Temperature as high as it will go and let the fan start first by it's self, then cut the compressor in. Once you got it going it's the compressor cutting in and out with the fan on constant.

That was the startup plan.. fan 1st.. I found a G.E. unit with knobs for 3 speed fan and separate cool setting..

The extra $100 for the Xantrex SW2000 may be the way to go then initially over my original SW1000 thought.. This is TX.. it isn't cool..

I was giving numbers for "best case".
Worst case: 5 Amps = start-up surge of 25 Amps @ 120 VAC. Convert to DC load and you get about 275 Amps all in one go. This would "flatten" 200 Amp hours of battery instantly.

And that is a big concern. With the very high DC current the Voltage "apparent" at the inverter can drop below the minimum and the system will shut down rather than start the A/C unit. The system Voltage of 12 is probably a bigger problem than the load itself. On a 24 Volt system those concerns would be greatly reduced (137 Amps potentially). On 48 Volts you wouldn't need to worry (68 Amps potentially).

Have you seen the thread about the mini-split A/C's? They have a soft start that almost eliminates this problem.
Although I still wouldn't be keen on running one off 12 VDC. If you're thinking of swapping inverters anyway (and you need to to run that) maybe it's time for a system upgrade?

Coot, wasn't trying to get on your toes, mine does pull more than 50 Amps. I have been wanting one of those Dometic Soft Start units to test, but at $350.00 on a $90.00 A/C is hard to justify. a 13,000 but unit on a Honda EU2000. There is a video of it somewhere.

as the guys indicated you will find that between the high surge turn on and the low power factor that you would need a high power good quality sine wave inverter. the sw2000 is borderline with its capacity and it may or may not work for you as it's hard to say. this also means a much larger battery bank and pv system to feed it as the high draws would dip the voltage on a small bank shutting down the inverter even if run for short time periods. even running a refrigerator is a royal pain in their requirements and they are somewhat similar to a very low btu a/c unit (well under 5000 btu). this is something you should think bigger on for an off grid pv system or go with a generator. if grid tied then just supplement as best as you can with solar.

albert,
you will also have the option of using a swamp cooler as, if i miss my guess, that area will have fairly dry air. swamp coolers use evaporation to help cool things and will have a fan to speed it along. no compressor could save you big on the power consumption. that item would be bought down in the midwest as the east is too humid to accommodate such a thing and therefore it is not usually available here in the east. the drawback is you need to keep it with water and in arid areas it could be scarce. not too sure of how much crud builds up either from high ppm values found in ground water. city water is high too, but not as high as many wells are.

albert,
you will also have the option of using a swamp cooler as, if i miss my guess, that area will have fairly dry air. swamp coolers use evaporation to help cool things and will have a fan to speed it along. no compressor could save you big on the power consumption. that item would be bought down in the midwest as the east is too humid to accommodate such a thing and therefore it is not usually available here in the east. the drawback is you need to keep it with water and in arid areas it could be scarce. not too sure of how much crud builds up either from high ppm values found in ground water. city water is high too, but not as high as many wells are.

I used one when I lived in Denver and about every other season it required pad replacements because of build ups, and that was on utility water. They are a good solution if the air is dry enough.

Ok, I've been there and done that, Lots of issues, but first My 1800 watt prosine inverter (has a 3000watt max capacity) runs my 5300 BTU AC just fine, and I've run it off of a hybrid 1400watt inverter (2800 or 3000watt surge) My setup is/was similar to yours in that I used 4 Golf cart batteries, originally I had @1000 watts of panels. I run a 24 volt system.

What I did was to build a 10x16 cabin with 13' height(sleeping loft), I built it in the shade, I built it knowing I would want to air condition it, so it has double pane windows and and 6" insulated walls, with 8 or 10" in the floor.

During the day after the batteries go into float I feel comfortable running the AC, The first hour may be a slight draw down of the batteries, as the Duty Cycle is 70-80% (the compressor runs 70-80% of the time) after the room is cooled off it runs30-50% depending on the outside air temps. I live in Missouri and heat typically runs with the sun, and we only hav 6-10 weeks of really hot temps. I normally work in the earlly evening and would run the AC on Energy saver for 2 hours and go to sleep, if I woke up due to it having warmed up too much I'd run the AC on timer for an hour and in the worse of times I'd run it again early in the morning.

The AC was sold by sears and was 10.3 rated, I see they have a 5200 with an 11 effiecency rating now. The fan comes on first in my unit and then a minute or so later the compressor kicks in, or if you have it on energy save the fan will turn off if your setting is above the room temp.

If you have shade... and a well insulated building.... It can be done...

...in Missouri.

Original Array, while I added panels to adventually bring this up to 1600 watts (on the golf cart batteries) the batteries capacity is really the limiting factor, the larger array only let me turn on the AC earlier in the day while the sun was shining.

Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites, Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol

Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites, Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol

Ok, I've been there and done that, Lots of issues, but first My 1800 watt prosine inverter (has a 3000watt max capacity) runs my 5300 BTU AC just fine, and I've run it off of a hybrid 1400watt inverter (2800 or 3000watt surge)

$975+ is a little steep for me for the Xantrex ProSine 1800..

What is the brand of the Hybrid 1400 Watt inverter?? Was it a PowerBright??

What I do with my A/C is I use the Generator for about 2 hrs before going to bed. Top up the batteries and Turn the A/C down as cold as I can get it ( Around 70 deg ). I have the thermostat knob marked at about 76 deg. When I shut the generator off and switch to the inverter I turn the knob up the A/C won't come back on till way up in the night, maybe 2:00 am and then it only runs a short period of time. You need to figure out how load shifting and power management works best for you. Sometimes I do the two hrs on the Generator early in the evening and shut it down for a couple hrs then less before I go to bed. Anytime your running the generator and your not using all the power you can it's a waste. Your Solar will fill you back in during the day.

As I said in my PM "...8.5Amp and 30.7V..." is not a 24V nominal panel, but a panel designed for grid connect or use with MPPT charge controller.

Math on the batteries, 800 amps only if you use them at 6volts, as 2 in series and 2 pairs paralelled, 12 volts at 400 amp, as a 24 volt string of 4 batteries, 24 volts at 200 amps.

Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites, Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol

I have a lttiile frigidaire 5k BTU unit I run very rarely. I run it on my eu1000 Honda genny. I sue the slow start method, run the engine on full throttle, no load, turn the fn on and let it spool if full for a few minutes, then turn the compressor on low. The Eu100 will barely start it,, but runs it fine. It draws ~550 wats running.

My guess is that you are going to be REALLY hard pressed to get any meaningful run time off nearly any 12 v battery set up. Even if it would run it, my guess is that any inverter will drop out due to low voltge shut down first. You could start it on the genny, and the a quick switch to the battery while the compressor is still running, then leave it running full bore so the compressor never shuts off.

That also clears up the battery issue.. (I confuse easy).. so realistically I should have 2 banks of 4 (total 8*6v) and then I would be 400ah rated in total.. hypathetcially I could run my AC for like 3 hours and be about +75% left in the bank..

I would go with the swamp cooler in a heartbeat, we used one in
colorado and could drop the temp from 80 to 69 degrees in about two hours in a 2000 SQ Ft. home. I wish I could run one in the NW. I would plan at least 2000 watt inverter 24 volt MIN.(with a good surge rateing) and plan on running off PV ,not batteries.....I am going to try this also but havent upgraded my inverter yet.

The newer swamp coolers dont use that much water, in our town in Gunnison Colorado water was like Gold. You learned not to waste a drop, and we did OK......Our well was 285ft down and another 100 ft. to our three story house
coming from the mid-west this was a culture shock.....

That also clears up the battery issue.. (I confuse easy).. so realistically I should have 2 banks of 4 (total 8*6v) and then I would be 400ah rated in total.. hypathetcially I could run my AC for like 3 hours and be about +75% left in the bank..

Right battery bank, but you'll need a minimum of 1000 watt array (panels) to support it.

Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites, Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol

I'm in hot/humid FL. Swamp coolers don't work here. So when the grid goes down, I drag out a 5000 BTU A/C unit. To make sure it works with my hardware, I did some testing.

First wanted to make sure it worked with a Yamaha EF2400iS generator.

With the fan on high, and the compressor engaged, draws almost 5A. It's rated at 600W, so the numbers are close.

After a few minutes I shut it off, then immediately tried restarting it. This is the worst case scenario, and not what you should do. Restarting too fast can stall the compressor as the pressure in the system is still maxed. Ideally, you should wait several minutes, allowing the pressure to drop. This isn't an issue when allowed to cycle normally. I wanted to challenge the generator.

This tiny A/C pulled over 18 AMPS starting current! My generator momentarily picked up RPMs, then dropped back to an idle.

The Xantrex Prosine 1800W inverter performed equally, if not better.

My intent is to use my 900AH battery bank at night for the A/C unit, and critical loads (fridge, some lights, small TV, computer, etc), and a combination of a 1000W solar array, and the generator with a 75A Iota charger, to replenish the energy used at night.

I had no problem cooling the master bedroom, bathroom, and short hallway with this A/C unit during the middle of Summer when the central A/C failed. After ~20 minutes, the room cooled down and the compressor cycled off. The blower only draws 0.2A.

I also agree a 1000W inverter wouldn't likely start it, or at least not restart it when there's a head pressure.

If swamp coolers work in your area, great! If not, it's still possible to use a window shaker.

I've found that these window A/C's burn a little more juice after they've been running a while, than when they first start.

If you have water, definitely go with an evaporative cooler!

Example: It turned unusually hot here (103 F). And with my setup (see sig) I could barely run one 5k and one 6k BTU A/C's between 10:30 am and 2:30 pm with no other loads. And even then, I was pulling 1 to 2 amps from the batteries in addition to what the panels were putting out. Granted, compressors were running constantly, non stop...